This error indicates that you have attempted to attach more than one SAN device using the same drive number.

If you are attempting to use the sanboot or sanhook commands to attach multiple different SAN drives, then you will need to specify explicit drive numbers. For example:

  sanhook --drive 0x80 iscsi:192.168.0.1::::iqn.2010-04.org.ipxe.chipmunk:boot
  sanhook --drive 0x81 iscsi:192.168.0.1::::iqn.2010-04.org.ipxe.chipmunk:data
  sanboot --drive 0x80

If you are attempting to use the sanboot or sanhook commands to attach a multipath SAN drive, then you will need to specify the full list of SAN URIs in a single command. For example:

  sanboot iscsi:192.168.0.1::::iqn.2010-04.org.ipxe.chipmunk:boot \
          iscsi:192.168.0.2::::iqn.2010-04.org.ipxe.chipmunk:boot

If you are attempting to replace an existing SAN drive then you must first use the sanunhook command to disconnect the existing SAN drive.